1. Field of the Invention
This invention relates to multiple-phase density flowmeters and materials analysis apparatus and, more particularly, to an x-ray multiple-phase flowmeter, density and fluorescent materials analysis apparatus and method.
2. The Prior Art
Historically, the measurment of the flow of fluids (both gases and liquids) may be categorized as encompassing (1) invasive measurement techniques and (2) non-invasive techniques. Invasive techniques utilize devices extending into the flow of the fluid and include probes, the introduction of markers, orifices and the like.
Non-invasive techniques externally measure a particular flow-dependent property such as changes in the optical, acoustic or electromagnetic properties of the fluid. Unfortunately, these latter techniques generally require a nearly transparent fluid and are not readily adaptable to a two phase or multiple-phase system. Multiple-phase systems are those for example, found in gas and fluid mixtures, steam-water systems or solid-fluid systems such as a slurry pipeline wherein coal particles are transported by being entrained in a gas or water stream.
Currently, the measurement of mass flow rates, fluid velocity and density in steam-water mixtures in boilers, nuclear reactors, and associated piping is difficult and, unfortunately, error prone. This is particularly true using the current invasive or non-invasive techniques. Present non-invasive techniques are not sufficiently refined to provide the desired accuracy particularly at each point in a cross section of a pipe or a vessel. However, increased demand for steam-driven turbine systems for electrical generators using nuclear fuel coupled with an increasing concern for nuclear safety has created a demand for increasingly accurate flow measurement for safety monitoring devices. Accurate flow measurement devices are also specified for conventional process instrumentation but, more especially for instrumentation for special purpose nuclear reactors and associated equipment designed to evaluate safety features and responses in the event of an accident, particularly a loss of coolant accident in a pressurized water nuclear reactor.
Increased emphasis is also being directed toward the use of coal-fired generating systems. It is, therefore, becoming increasingly important to be able to transport coal over long distances, up to several hundred miles, from the coal deposits to the power generating station. Currently one of the most economical techniques is the slurry pipeline system. Accordingly, it is also important to be able to accurately measure the mass flow rate of the coal particles in the slurry pipeline. The use of invasive techniques in slurry systems, is practically useless because of the difficulties created by the particles of coal in the fluid stream. For example, probes become clogged and restriction orifices create areas of sedimentation thereby destroying the utility of an invasive technique for measuring such a two phase system.
Other applications could also advantageouly utilize a mass flow rate measurement system wherein a multiple-phase system is being measured. Measurement of mass flow rates should also lend itself to density and/or concentration measurements. This could be useful in reactors, both chemical and nuclear, as well as certain process streams.
Accordingly, it would be a significant advancement in the art to provide a mass flow rate meter apparatus particularly one using a non-invasive measurement technique. Another advancement in the art would be to provide an apparatus and method whereby an essentially single-phase system may be accurately measured by the controlled injection of a second phase into the system and thereafter non-invasively measuring the two phase system. It would also be an advancement in the art to provide an apparatus and method for measuring density and phase concentrations in a multiple-phase system. Another advancement in the art would be to provide an apparatus and method for analyzing chemical elements by non-invasive, x-ray fluorescent techniques. It would also be an advancement in the art to provide an apparatus to reconstruct the cross sectional flow and density distribution of phase components in a flow system. Such an apparatus and method is disclosed and claimed herein.